Tycho/Migration Howto

This page is intended to give existing projects a jumpstart for setting up a Tycho build.

While each project is different, there are some common steps:

Scaffolding: Generate pom.xml files

Maven needs pom.xml files to drive the build (one pom.xml file per plugin/feature). See Generating POM files on how to generate an initial skeleton for these files.

Manual adjustments

In the generated top-level (parent) pom.xml, it's a good idea to globally define the tycho version to use

<properties>
  <tycho-version>0.20.0</tycho-version>
</properties>

so you can reference it using ${tycho-version} anywhere in the child pom.xml files e.g. when configuring tycho plugins. See maven project inheritance.

In case you have deeply nested projects and used several generate-poms invocations, add a top-level parent pom.xml and reference it as parent from the intermediate parent poms. Also, adjust the modules to be built (see maven project aggregation).

Adding p2 repositories to resolve external dependencies

Almost every project has external dependencies it needs to compile against. Add all p2 repositories you need for compilation or runtime in the parent pom like in the following snippet:

<repositories>
   <repository>
      <id>eclipse-juno</id>
      <layout>p2</layout>
      <url>http://download.eclipse.org/releases/juno</url>
   </repository>
</repositories>

See Tycho Reference card

Run the build

Run mvn clean install in the directory of the parent pom.

Getting tests to run

If your test bundle symbolic names end with .tests, the pom generator will accordingly define

<packaging>eclipse-test-plugin</packaging>

This will tell Tycho to scan for test classes and execute them during build. Note that by default, test class scanning is using naming convention

**/Test*.java **/*Test.java **/*TestCase.java

to find tests.

For details, see the Tycho Surefire docs

Tips:

• To skip test execution temporarily, use commandline option -DskipTests
• To debug tests, use commandline option -DdebugPort=8000
• In case you are using SWTBot, see Running SWTBot tests with Tycho
• How to run a test suite
• By default, only the transitive dependencies of the test plugin make up the test runtime. See How to add implicit dependencies to the test runtime if you have implicit (runtime-only) dependencies.

Generating source bundles and features

See the Tycho Reference Card on how to configure source bundles and feature generation in your parent pom. See also reference documentation for source bundles and source features.

Building a p2 repository

Once you have a build with plugin and features up and running, you can create a p2 repository for these bundles and features. For this, create a pom.xml with

  <packaging>eclipse-repository</packaging>

, add it as a module to the parent pom and place a category.xml file in the root. See eclipse-repository for details.

What if I'm stuck?

Check all the information sources (sample projects, reference docs, mailing list, tutorial) available from the Tycho documentation